Packaging techniques for semiconductor devices, such as transistors, integrated circuits, or optoelectronic devices including light-emitting diodes (LEDs) and laser diodes (LDs), include using glue or solder paste to connect semiconductor chips and package substrates while flip-chip techniques are performed by using metal bumps to connect semiconductor chips and package substrates.
However, in the process of fixing the semiconductor chips with glue and solder paste or in the flip-chip package processes, the process temperature has to be increased to above 150 degrees Celsius. During the thermal connection processes at such a temperature, the electricity properties of the semiconductor devices are easily damaged.
In addition, when the semiconductor optoelectronic devices are applied in a large or small backlight module or illumination module, the semiconductor optoelectronic devices need to provide sufficient light export flux to generate sufficient brightness and illumination for the modules. Therefore, these semiconductor optoelectronic devices usually have to be operated at high input power. However, the high input power causes an abrupt increase of the temperature of the semiconductor optoelectronic devices, thereby degrading the operational efficiency of the semiconductor optoelectronic devices, and even burning the semiconductor optoelectronic devices due to the high temperature.
Currently, in order to resolve the poor heat-dissipating efficiency issue of the semiconductor illumination module, the module is typically cooled by fans set in the module or by increasing the heat dissipation area. However, these techniques cause many problems. For example, regarding setting fans in the module, the vibration caused by the operation of the fans results in the lights flickering, and the fans consume additional power. Regarding increasing the heat dissipation area, the cost of the heat dissipation material of the larger semiconductor illumination module is greatly increased. In addition, although the heat dissipation bulk can be composed of metal with high thermal conductivity, such as Al or Cu, for achieving the effect of rapidly transmitting heat, glue is used to connect the semiconductor illumination device and the heat dissipation bulk, and the thermal conductivity of the glue is much lower than that of the pure metal. As a result, the heat generated during the operation of the device mostly accumulates at the connection interface, thereby making the heat dissipation bulk less effective.
Another technique is provided. In the technique, a front side of a semiconductor device is firstly pressed into an adhesive tape, and a metal reflective thin film and a metal heat dissipation bulk are plated on a rear side of the semiconductor device. However, the inventors discover that when a large adhesive tape is adhered with a large semiconductor device, air bubbles are easily formed at the adhesive interface. As a result, the metal reflective thin film and the metal heat dissipation bulk plated on the adhesive tape are non-uniform. In addition, during the metal plating process, it is very easy for the adhesive tape to expand with heat and contract with cold. Therefore, the metal reflective thin film on the adhesive tape cracks very easily, thereby greatly reducing the yield.